What fuel pressure??

[MaccyD]

I just fitted my fuel pressure regulator and was wanting adive for wht pressure to run. I will be running 1bar on standard ct9, it is sat at 3.7bar atm and im thinking i can prob tweek it down a bit.

 

[lleey2k4]

I set mine at 3 bar like everyone does but just to get you to a RR to get it setup.

 

[MaccyD]

i dont get how it needs setting up :S surely the fuel pressure is set high and fuelling is controlled by injectors so it doesnt exactly need to be precise....?????

 

[Dave@TM-developments.com]

The more pressure behind the injectors the more they will allow in

 

[Jay]

The regulator will physically increase the pressure in the rail. The injectors will still operate as normally but the increased pressure will force more fuel into the engine.

Each engine/setup will operate differently so it's best to take other people's settings as only a guideline and get your tuner to finetune as he sees fit.

Get a wideband stuck on her and you'll be able to set it up fine buddy.

 

[MaccyD]

i see, so i should prob back it off to around 3bar then??? its only til tuesday when im on the dyno

 

[Jay]

Usually safer just to potter about till you get a pro to measure it mate. No point risking an engine over a few days wait if you know what I mean.

 

[MaccyD]

well overfuelling isnt gonna cause a problem. im only running 0.5 bar until i get them to set up my safc properly (which isnt in yet btw) but yeh i dont see why i need to get it fully setup, people must know what pressure to sit at roughly, im after a safe ballpark figure to last me a few days as i think 3.7 bar is too high.

 

[gv1.3]

mine fuels 37-38psi at idle and Im running just under 1 bar

 

[TurboDave]

well overfuelling isnt gonna cause a problem. im only running 0.5 bar until i get them to set up my safc properly (which isnt in yet btw) but yeh i dont see why i need to get it fully setup, people must know what pressure to sit at roughly, im after a safe ballpark figure to last me a few days as i think 3.7 bar is too high.

Excessive overfueling will cause the unburnt fuel in the cylinders to leak past the rings and mix with your oil in the sump, taking away its lubricatory properties and doing damage to your engine, this is called "Borewash".

 

[gv1.3]

this is called "Borewash".

nice bloke.. sells some good stuff on here

 

[TurboDave]

nice bloke.. sells some good stuff on here

Dave Borewash lol, the best name I have ever heard Dave called is Dave Warbrush it was hillarious.

 

[ChrisGT]

Got my car dyno'd yesterday to set fuel pressure regulator up for 1Bar on the CT9. It was idling at 2.5ish bar for 14psi (just under 1Bar). We also had it at 15.5psi and it was running a fair bit more fuel pressure, made considerably more power too (+10lbft, +10hp atw). The bloke said the fuelling was OK, obviously rich down low and he kept it slightly rich top end for safety reasons.

But its not really the way to go, such a crude method! He said a piggyback would be better suited to the car and you'd get a much better tune (obviously). But he said FPR wasn't a dangerous way of doing things, just not the best for performance...1Bar is fuuun! But my I think my JAM FCC is borked, so no more 1Bar for me!

 

[MaccyD]

well i have the fuel pressure regulator and also an apexi s-afc so thats the main thing im having setup on the dyno.

 

[weakboy2]

well your best bet is to set it high on the dyno day then use the safc to trim it back a bit

 

[ChrisGT]

Like above, the tuner will most probably set the FPR to run rich then trim it down at the rpm points via the SAFC. As for what pressure to run in the mean time, set it to standard pressure and drive off boost until you get it properly setup mate.